Field of the Invention
The present disclosure relates to a method for recovering the efficacy of solar cell modules and a portable device thereof.
Description of Related Art
Solar cell is an environmentally friendly energy, which can directly transform solar energy into electrical energy. Existed solar cells, based on the main material, can be divided into silicon-based semiconductor solar cells, dye-sensitized solar cells, organic solar cells and other types of solar cells. Silicon-based semiconductor solar cell has the highest photovoltaic conversion efficiency and a low-cost advantage.
However, silicon substrates of silicon-based semiconductor solar cells usually have higher density of lattice defects and higher concentration of impurities. These impurities, such as oxygen, may further combine with the dopants, such as boron, doped into the silicon substrate to form positively-charged compounds, such as boron-oxygen compounds. In this way, in electricity-generating process of solar cell module having silicon-based semiconductor solar cells, these lattice defects or the positively-charged compounds will capture the electrons generated by light, which is called light-induced degradation (LID) phenomena. These phenomena will dramatically decrease photovoltaic conversion efficiency of solar cell modules, and the phenomena will be more seriously as increasing usage time. Generally, after used for 1 year, the photovoltaic conversion efficiency of the solar cell modules decreases to a degree of 3% to 20%. Therefore, a method for recovering the efficacy of solar cell modules and a device thereof are needed to solve the aforementioned problems.